ok. well here we go. now that you have a tach you can turn the rpm up to 3600 rpm or slightly above no load. then you need to look at the fluid flow schematic in the wsm to see were the possible leaks of high pressure circuit cold be. like bypass valves poppet valve and coast valve unloader. when yo u have checked each of these then you can proceed into the valve plates and pump and motor. you aren't to far off of spec so i would still consider getting super udt and k brand filters anyway. if you want you can check the valve plates before you change the oil because you will need to refresh the oil after you open it up anyway. but i would still check the bypass valves first.
Kubota RTV 900 transmission problem - hardley moves in gear!
- Thread starter PACKASAURAS
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wow it sounds like the PO has tampered with everything. all that means is every screw and nut on any valve or servo etc might have been adjusted. it is going to be a bit of sherlock holms work but has to be done. you are doing a great job. now you need to find all of the other places and see if you can tell what the PO did.
http://www.nettractortalk.com/forums/showpost.php?p=104534&postcount=9
This seems to be a good starting point.
This seems to be a good starting point.
No change, still 3000psi. Screw seems very loose. The post linked above mentioned that, but it's almost like nothing is there. It was not set according to the post, I found it nearly bottomed out. Looking at the drawings seems like it would make the piston mentioned by the op operate sooner. Lowering the engagement RPM. Same as adjusting the lever linkage.
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the servo screw sounds like a real important adjustment but all it really does is center the servo piston so that the swash plate goes to neutral between forward and reverse. shouldn't affect pressure.
yep! proceed with caution. use your test set to read pressures.
I don't have a test set.
Ok. It's set per the post.
sure you do. your pressure gauge.
in the page you posted it describes how to adjust. compress the spring and adjust the screw. use a padded jaw in the vise. if you screw it up you can buy a new one. go slow-adapt,improvise,overcome.
get a cheap c clamp from HF. drill a hole through the dead end of the clamp big enough to get a screw driver through to adjust the poppet. use small piece of copper pipe as a sleeve to compress the spring and a copper oil plug gasket as a pad on the other end. turn the c clamp to compress the spring and reach through the hole to adjust the screw then remove and measure and install to test pressure. repeat until spec.
I beat you to this clamp idea. Also got the relief valve into spec, uggg no pressure change. Still 3000max. Where to next? Pretend I have the super duper fluid and filters, that is last stage before total replacement.
i would be surprised if the fluid is the immediate problem. but inferior fluid could be the cause of premature wear that became the problem. if adjusting the valve didn't change anything then you probably have a leak in the valve plates on the pump or bad pump or motor plungers. are you sure you have found all of the bypass valves in the hydraulic schematic???
has the transmission ever overheated???
has the transmission ever overheated???
different viscosity could affect pressure.
The overheating is a possibility. There's only one valve left but I think it's hidden in the rear cover.